A user environment, such as a residence or an office building, for example, may be configured using various types of load control systems. A lighting control system may be used to control the lighting loads providing artificial light in the user environment. A motorized window treatment control system may be used to control the natural light provided to the user environment. An HVAC system may be used to control the temperature in the user environment.
Each load control system may include various control devices, including input devices and load control devices. The load control devices may receive digital messages, which may include load control instructions, for controlling an electrical load from one or more of the input devices. The load control devices may be capable of directly controlling an electrical load. The input devices may be capable of indirectly controlling the electrical load via the load control device.
Examples of load control devices may include lighting control devices (e.g., a dimmer switch, an electronic switch, a ballast, or a light-emitting diode (LED) driver), a motorized window treatment, a temperature control device (e.g., a thermostat), an AC plug-in load control device, and/or the like. Examples of input devices may include remote control devices, occupancy sensors, daylight sensors, glare sensors, color temperature sensors, temperature sensors, and/or the like. Remote control devices may receive user input for performing load control. Occupancy sensors may include infrared (IR) sensors for detecting occupancy/vacancy of a space based on movement of the users. Daylight sensors may detect a daylight level received within a space. Glare sensors may be positioned facing outside of a building (e.g., on a window or exterior of a building) to identify the position of the sun when in view of the glare sensor. Color temperature sensors determine the color temperature within a user environment based on the wavelengths and/or frequencies of light. Temperature sensors may detect the current temperature of the space.
As described herein, current load control systems implement many input devices, including a number of different sensors. The use of many input devices causes the load control systems to take readings from multiple different types of devices and control loads based on many different types of input.
The input devices in current load control systems may also be inefficient for performing their independent functions in the load control systems. For example, current load control systems may receive input from a glare sensor that indicates that glare is being received from the sun, but load control systems may attempt to reduce or eliminate the amount of glare within the user environment using prediction algorithms to predict the portions of the user environment that are being affected by glare. Attempting to reduce or eliminate the amount of glare within the user environment using these prediction algorithms may be unreliable.
The daylight sensors and the color temperature sensors in the load control systems may also be inefficient for gathering accurate information for performing load control. Current use of daylight sensors and color temperature sensors rely on the accuracy of the location of the sensor for detecting how the intensity of light affects the user environment. It may be desirable to have more accurate ways of determining how the actual intensity and color of light provided within the user environment affects a user within the environment.
As the occupancy/vacancy sensor generally senses the presence or absence of a person within the user environment using passive infra-red (PIR) technology, the occupancy/vacancy sensor may fail to detect the occupancy of a room due to the lack of movement by a user. The occupancy/vacancy sensor senses the presence of a person using the heat movement of the person. The vacancy sensor determines a vacancy condition within the user environment in the absence of the heat movement of a person for a specified timeout period. The occupancy/vacancy sensor may detect the presence or absence of a user within the user environment, but the sensor may fail to provide accurate results. For example, the occupancy/vacancy sensor may detect other heat sources within a user environment and inaccurately determine that the heat sources are emanating from a person. Further, the occupancy/vacancy sensor is unable to identify a person that is not moving, or that is making minor movements, within the user environment. Thus, it may be desirable to otherwise determine occupancy/vacancy within a user environment.
As complex load control systems generally include many different types of input devices for gathering information about a load control environment, the processing and communicating of information in such systems can be inefficient. Additionally, as the information collected by many input devices may be inaccurate, the control of loads according to such information may also be inaccurate.